Porcelain



Patented an it, 11923.

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CHESTER C. TREISOHEL, F SOHENECTADY, NEW YORK, ASSIGNORI TO GENERAL ELEC- ER-TC COMPANY, A CORPORATION OF NEW YORK.

PORCELAIN.

Elle Drawing.

T 0 all whom it may concern Be it known that l, CHESTER C. Tnnrsonnn, a citizen of the United States, residing at Schenectady, in the county of Schenectady,

' State ofNevv York,'have invented certain new and useful Improvements in Porcelain, of which the following is a specification.

The present invention comprises an imroved ceramic material, which is particuarly useful as a high tension electrical insulator.

Porcelain commonly consists of a mixture of clay, silica and feldspar. I have discovered that the mechanical and electrical'in- 1 sulatin properties of porcelain may be marked y improved by introducing certain fluxing silicates into the porcelain other than feldwansuch for example, as the mineral beryl. This material may be substituted totally or in part for either the usual feldspar or silica content.

The percentage of fluxing silicate may vary materially. I have obtained good results with percentages of beryl ranging from five to thirty-five per cent.

The following green or unfired mixture constitutes an example of my invention as embodied in a porcelain suitable for electrical line insulators.

'30 Clay"; Q. 291 parts. Silica parts. lFeldspar 144 parts.

Beryl 130 parts.

Application mm a... e, 1921. Serial rm. 476,084.

This mixture is subjected to the usual treatment accorded to porcelain mixtures, 5 and finally fired in the usual way to a term perature corresponding to Segar cone 10.

Porcelain having the above composition shows upon test the following improvement over first quality electrical porcelain. 4

Approximate improvement-Per cent.

Dielectric strength 16.5 Transverse 22.5 Resistance to impact 44.0 Resistance to temperature changes- 132.0

' CHESTER C. TRETSCHEL. 

